The term 'Eastern Sash' is a type of traditional Japanese clothing. It is a sash that is worn around the waist and is typically made of silk or cotton. The OBI, which is a three-letter word, is the belt that is used to tie the sash in place. The OBI is usually brightly colored and can be decorated with intricate patterns. It is an important part of the traditional Japanese dress and is often seen in formal occasions.